Fluid dispensing apparatuses for dental engines



Dec. 25, 1962 K. H. LIEDBERG ETAL 3,069,776

FLUID DISPENSING APPARATUSES FOR DENTAL ENGINES Filed April 21, 195s 3 Sheets-Sheet 1 Fig. 5

INVE

w #77] ATTORNEY Dec. 25, 1962 Filed April 21, 1958 K. H. LlEDBERG ETAL 3,069,776 FLUID DISPENSING APPARATUSES FOR DENTAL ENGINES 3 Sheets-Sheet 2 m 4 JT My 4 V 56 2 25, 1962 K. H. LIEDBERG ETAL 3,06

FLUID DISPENSING APPARATUSES FOR DENTAL ENGINES 3 Sheets-Sheet 3 Filed April 21, 1958 United States atent O T 1 3,069,776 FLUID DISPENSING APPARATUSES FOR DENTAL ENGINES Kurt Herman Liedberg and Stig Folke Adrian Peterson, Shara, Sweden, assignors to Atlas Copco Alrtieholag, Nacka, Sweden, a corporation of Sweden Filed Apr. 21, 1958, Ser. No. 729,775 4 Claims. (Cl. 3228) This invention relates to a fluid dispensing apparatus for dental engines. An apparatus of this type may preferably be combined with a dental engine stand, for instance of the type described in the assignees co-pending US. application, Serial No. 685,921, filed September 24, 1957, now Patent No. 2,942,757, 'by K. H. Liedberg et al. The fluid dispensing apparatus according to the invention may, however, also be combined with dental engine stands of other types which include a device responsive to the power consumption by a dental engine. The dental engine stand described in the above numbered application includes a pressure reduction valve device carrying a micro-switch which is operated to close an electric circuit as soon as power is consumed by any of a number of dental engines fitted to the stand. One object of the present invention is to provide a fluid dispensing apparatus which is of a simple construction and which automatically supplies fluid to a dental engine for cooling the tool driven by said engine and the tooth or the like operated on with said tool. The fluid may comprise water, a mixture of water and compressed air, or compressed air only. A further object of the invention is to provide a dispensing apparatus including a receptacle for spray water which is easily removable and attached. Still further objects of the invention will be apparent by the following specification, clairns and drawings which illustrate by way of example one embodiment of a fluid dispensing apparatus according to the invention.

For the above and other purposes We provide a fluid dispensing apparatus for dental engines comprising in combination a valve device, means for supplying compressed air to said valve device, a liquid receptacle removably attached to said valve device, a liquid conduit communicating with said receptacle and leading to a dental engine, a casing forming an air chamber in said valve device communicating with the receptacle, an air passage from the valve device to said air chamber for producing air pressure in the air chamber to press liquid from the receptacle to said dental engine, and means for removing said air pressure upon interruption of power consumption of the dental engine.

In the accompanying drawings FIG. 1 is a side view of a fluid dispensing apparatus according to the invention, and FIG. 2 a section on line II-II in FIG. 1. FIG. 3 is a section on line III-III in FIG. 2. FIG. 4 is a side view and partial section of a dental engine stand with which the apparatus accordingto FIGS. 1-3 may be combined, and FIG. 5 is a section and partial side elevation of a throttle valve device combined with the apparatus and arranged on the dental engine stand illustrated in FIG. 4.

The dental engine stand illustrated in FIG. 4, which may be of the design described in K. H. Liedbergs et al. co-pending application, Serial No. 685,921, now Patent No. 2,942,757, consists of a housing 1 which is carried on a post 2, or on a bracket extending from a wall or from Patented Dec. 25, 1962 the conventional dental unit which carries the various tools and accessories used by a dentist. This dental engine stand is adapted for use in connection with pressure fluid driven dental engines 3 but the invention is not limited to the combination with dental engine stands for such engines and may be used in connection with pressure liquid driven or electrically driven dental engines also.

The illustrated casing 1 contains a pressure reduction valve device 4 and for each dental engine an automatic valve device 5. Furthermore, the casing contains a distributing valve device 6 for the cooling or spraying fluid and in the front portion a holder 7 for each dental engine 3. The dental engine 3 may be of the type described in the assignees co-pending application, Serial No. 566,- 654, filed February 20, 1956, now Patent No. 2,855,671, by Lundgren et al. Compressed air is supplied to the pressure reduction valve device 4 through a hose 8 and compressed air of reduced pressure controlled by the adjustment of a suitable control wheel 9 flows from the pressure reduction valve device 4 through conduits 10 to each one of the automatic valve devices 5. A lever 11 controls a shut-off valve in the device 5 to open or shut off an air passage communicating through a hose 12 with the dental engine 3. When the lever 11 is in open position the supply of compressed air to the dental engine 3 is opened as soon as the dental engine 3 is lifted from a trip lever 13 which carries the holder 7 and operates the stem 14 of an automatic check valve in the automatic valve device 5. When the dental engine 3 has been removed from the holder 7 operation of the dental engine is controlled by a finger-tip control 15 at the dental engine. The illustrated dental engine stand 1 is designed for two dental engines and a hose 16 and 17, respectively, leads from the distributing valve device 6 to each dental engine 3.

The fluid dispensing apparatus illustrated in FIGS. l-3 and 5 consists of a valve device comprising a housing 20 provided with a clamp 21 for clamping the housing to the post 2 carrying the dental engine stand. The housing 20 contains a valve casing 22, 23 accommodating a pressure reduction valve and an electro-magnetic valve. The pressure reduction valve consists of a valve member 24 movable in a bore 25 and having a square or other non-circular stem 26 guided in a bushing 27 and pressed against membrane bellows 28 by a spring 29 provided in an extension 3% of the bore 25. The membrane bellows 28 is loaded by a helical spring 31 the tension of which may be adjusted by means of a knob 32 screw-threaded on an extension 33 of a cover 34 enclosing the membrane bellows 28.

Compressed air is supplied to the valve casing 22 through a hose 35 branched off from the hose 8 and fitted to a nipple 36 which through a bore in the casing 22 communicates with the extension 39 of the bore 25. Passages 37 in the bushing 27 communicate with a passage 38 in the casing 22 which through a passage 39 communicates with a chamber 40 at one side of the membrane bellows 28 and furthermore through a passage 41 with a bore 42 through an opening 43 controlled by an electromagnetically operated valve member 44 disposed in the casing 23. The bore 42 communicates through a passage 45 with an air chamber 46 in a head '47 secured to the underside of the housing 20 by means of screws 48. The electro-magnetically operated valve member 44 has a valve surface 4? which cooperates with a seat 50 and controls an outlet passage 51 leading to a muffler 52 provided with outlet openings at 53. The passage 51 normally communicates with the bore 42 when the valve member 44 is pressed towards the opening 43 by a spring 54. Energization of the coil 55 in the casing 23 moves the valve member 44 towards the seat 50 and uncovers the opening 43. The coil 55 is connected by an electric cable 56 to a micro-switch 18 in the dental engine stand. The micro-switch is operated by a valve stem 19 disposed in the pressure reduction valve device 4. When a dental engine 3 is operated the pressure drop in the pressure reduction valve device 4 moves the stem 19 so as to operate the micro-switch 18 to close an electric circuit through the coil 55.

The head 47 carries a receptacle 57 for distilled water which is fitted to the head 47 by means of two pins 58 engaging bayonet openings 59 in the receptacle 57. An O-ring 60 provides a seal between the receptacle 57 and the head 47 to prevent escape of compressed air from the chamber 46. 61 indicates an airand water-tight opening in the receptacle covered by a suitable transparent material such as Plexiglas or the like. 62 is a float which when visible through the opening 61 indicates the amount of distilled water remaining in the receptacle 57. A pipe 63 fitted in the bore 64 in the head 47 projects towards the bottom of the receptacle 57 and communicates with a passage 66 in the head 47 which through a hose 67 is connected to a throttle valve casing 68. A further passage 69 in the head 47 forms a communication between the chamber 46 through a hose 70 and the throttle valve casing 68. The throttle valve casing 68 is secured to the dental engine stand by means of a bracket 71 and a screw 72. The casing 68 contains a throttle valve member 73 which has a screw-threaded portion '74 engaging screw threads 75 in a bore '76. A spindle 77 carrying the valve member 73 and a knob 78 may be turned to operate the valve member 73 which cooperates with a bore 79 communicating wit-h a passage 80 in the casing 63 leading from the hose 76 to a hose 81. The passage 79 may be brought into communication with the hose 67 through the bore 76 by opening the needle valve 73. The hose 81 conveys a mixture of water and compressed air to the distributing valve device 6 from which valve device said mixture is conveyed through the conduits 16 or 17, respectively, to the dental engine 3 which is momentarily in action and lifted from its holder 7.

The operation of the above described apparatus is as follows:

Before the apparatus is taken into use the receptacle 57 is removed and filled with distilled water. The receptacle is then attached to the head 47 by means of the bayonet fitting 58, 59. Compressed air is supplied to the extension 30 of the bore 25 through the hose 35 and the knob 32 is set so that a desired reduced air pressure is obtained in the space at and the passage 41. The coil 55 is unenergized and the valve member 44 is pressed by the spring 54 to keep the opening 43 closed, When the dentist has removed the dental engine 3 from the holder 7 and presses the control 15 to start the engine a pressure drop is produced in the pressure reduction valve device 4 which causes the stem H to operate the micro-switch 18. The micro-switch then closes the circuit from a suitable electric source through the cable 56 and the coil 55which is energized and moves the valve member 44 towards the seat 50 so that the venting passage from the chamber '46 is closed and the opening 43 is uncovered. (In connection wit-h electric dental engines the closing of the circuit to the engine by the dentists foot-switch may replace the above mentioned micro-switch for closing a circuit to the coil 55'.) Compressed air of reduced pressure is then supplied through the passage 41, the bore 42 and the passage 45 to the chamber 46 and presses water from the receptacle 57 through the pipe 63, bore 64, passage 66, hose 67 to the bore 76 in the throttle valve casing 68.

According to the setting of the valve member 73 more or less water is then supplied from the bore 76 through the bore 79 to the bore in which it is mixed with compressed air supplied from the chamber 46 through passage 6? and hose 70 to the passage 80. The mixture of water and compressed air in the passage 80 flows through the hose 81 to the distributing valve device 6 and from said valve device through the hose 16 or 17, respectively, to the dental engine at present in operation and produces a spray of finely divided water and air around the tool and the object worked upon with the tool, for instance a tooth. When the dentist releases the control 15 and thereby stops the engine the micro-switch breaks the circuit through the coil 55 and the air chamber 46 is then vented to the atmosphere silently through the mufller 52.

The above described fluid dispensing apparatus should be considered only as an example and the details of the invention may be modified in various different ways without departing from the scope of the following claims. A shut-01f valve may for instance be provided in the hose 70 when it may be desired to spray with water only. It is also obvious that if the valve member 73 is closed no water is supplied through the spray fluid tube 16 or 17, respectively, which is then only supplied With air.

What we claim is:

1. A pressure fluid driven dental engine having a fluid dispensing apparatus attached thereto, said apparatus comprising in combination a support, a liquid receptacle carried by said support, a liquid conduit communicating with said receptacle and leading to said dental engine, said conduit terminating in liquid spray means mounted on said dental engine, an air passage in said support communicating with a source of air pressure and with said receptacle for supplying air pressure on the liquid in the receptacle, means on said support for controlling flow of air from said passage to said receptacle, means for controlling flow of pressure fluid through said engine for driving a rotary tool, and means on said support operable in response to flow of pressure fluid through said engine for operating said flow controlling means to admit air pressure to said receptacle.

2. A pressure fluid driven dental engine having a fluid dispensing apparatus attached thereto, said apparatus comprising in combination a support, a liquid receptacle carried by said support, a liquid conduit communicating with said receptacle and leading to said dental engine, said conduit terminating in liquid spray means mounted on said dental engine, an air passage in said support communicating with a source of air pressure and with said receptacle for supplying air pressure on the liquid in the receptacle, 9. pressure reduction valve device on the support in said air passage, an air chamber on said support communicating with the receptacle, a part of said air passage leading from said pressure reduction valve device to said air chamber for providing air pressure in the air chamber to force liquid from the receptacle to the spray means on the dental engine, an automatic valve device on said support in the air passage to the air chamber, a vent passage in said automatic valve device leading from the air chamber, said automatic valve device being operable in response to pressure fluid flow to the dental engine to open said air passage to said air chamber when such fluid flow occurs and to close such passage and to open said vent passage when said fluid flow is interrupted, and means for controlling flow of pressure fluid through said engine for driving a rotary tool.

3. An apparatus as defined in claim 2 in which a muflier is provided in said vent passage.

4. A pressure fluid driven dental engine having a fluid dispensing apparatus attached thereto, said apparatus comprising in combination a support, a liquid receptacle can ried by said support, a liquid conduit communicating with said receptacle and leading to said dental engine, said conduit terminating in liquid spray means mounted on said dental engine, an air passage in said support communicating with a source of air pressure and with said receptacle for supplying air pressure on the liquid in the receptacle, a vent passage, means on said support for controlling flow of air from said air passage to said receptacle and from said receptacle through said vent passage, means for controlling fiow of pressure fluid through said engine for driving a rotary tool, and means on said support operable in response to flow of pressure fluid through said engine for operating said flow controlling means to admit air pressure to said receptacle.

References Cited in the file of this patent UNITED STATES PATENTS Henschel June 10, 1941 Siegel Aug. 19, 1941 Broussard et a1. Nov. 28, 1950 Norlen Jan. 5, 1954 

